1. Field of the Invention
The present invention relates to a water-soluble, antimicrobial active polymer, and more particularly, to a water-soluble polymer with antimicrobial activity, resulting from introducing an antimicrobial active compound into a water-soluble polymer. The present invention also relates to an ink composition comprising the water-soluble, antimicrobial active polymer.
2. Description of the Related Art
Generally, antimicrobial agents are applied to products that have frequent contact with water such as fibers, shoes, sponge gourds, and medical goods. Such antimicrobial agents are designed to have washing resistance or water-insoluble characteristic in order to maintain antimicrobial effects. For this reason, such antimicrobial agents had not been applied to water-soluble ink compositions.
Ink compositions comprise a colorant, a solvent and an additive. When stored for a long duration, ink properties and storage stability of ink compositions deteriorate due to reproduction and growth of bacteria in the ink. For this reason, an antimicrobial agent is separately added to ink compositions. Conventionally, organic compounds such as 1,2-benzisothiazolin-3-one (BIT) and methyl 2-benzimidazole carbamate (Carbendazim) are widely used as antimicrobial and preserving agents. They are separately added to ink compositions in an amount of 0.05–0.5% by weight for the purpose of extended storage duration. However, a nozzle is easily clogged due to ink coagulation and the homogeneity of ink droplets cannot be easily secured. Furthermore, when human skin is in contact with such ink compositions, skin irritation may occur. Therefore, handling property is deteriorated. Meanwhile, in case of using another antimicrobial agents with lower antimicrobial activity to overcome these problems, extended storage stability is decreased. Furthermore, it is difficult to select dyes or pigments which are well compatible with such antimicrobial agents. As a result, an optimal color quality cannot be easily accomplished.